Monday 22 October 2012 12.50 EDT
First published on Monday 22 October 2012 12.50 EDT

Media regulator Ofcom has criticised Channel 4's exclusive airing of the film trailer for Ridley Scott's Prometheus, which used Twitter to publicise viewer feedback, after deciding that it blurred the lines between advertising and editorial.

The special promotion involved the trailer being aired in an ad break during the US spy series Homeland in May, with Twitter feedback encouraged and aired in a subsequent commercial break.

Channel 4 branded the promotion with its logo and one of its most well-known continuity announcers handled the voiceover, which also included telling viewers to buy tickets to the film.

Ofcom received a complaint that the promotion totally confused the viewer about whether they were watching an impartial continuity announcement or a paid advertisement.

The regulator agreed, telling Channel 4 it had concerns that the distinct voice of the announcer, the broadcaster's logo and language used in the advert suggested the channel's ownership and endorsement of the material.

"In Ofcom's view, such viewer interaction is more commonly associated with television programmes than with advertising," the regulator said. "We consider that the presentation style of the Prometheus material risked confusing viewers in respect of it status."

With regard to the Twitter element of the campaign, Ofcom concluded that it might have been unclear to viewers whether they were watching a selection of tweets selected for editorial reasons by Channel 4 or for advertising purposes.

Channel 4 defended the promotion, arguing that there was a clear contrast between the channel identification and the start of a commercial break.

However, Ofcom responded that: "Simply because material appears in a break between programmes is not sufficient to identify it as advertising."

Channel 4 said that the campaign had received approval by Clearcast, which pre-vets TV ads to give advice on whether there are likely to be any issues with the advertising code.

The broadcaster added that changes to the broadcast code of advertising practice – the rules which govern TV ads – could lead to possible confusion over what broadcasters needed to do to adequately distinguish between editorial programming and advertising airtime.

Channel 4 has decided to implement a new internal policy to stop a repeat of the issue.

Steps now include the broadcaster's legal and compliance team having to sign off any ads which might potentially blur the lines between editorial and advertising; a caption stating "This is a Channel 4 advertising premiere"; and any announcer who works on a TV ad will not be used on a Channel 4 service on the day the ad is broadcast.

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